I admit, I did not know that. But in this case we as people are still using things of the universe as a method to develop a system. We use the system for communication, record keeping, and various other tasks that enable our race to evolve. The bottom line is the universe is made up of DIFFERENT things. And I emphasize different because if everything was the same we would not exist. We are able to think, remember, communicate because we can compare and relate one thing to another. By relating different things we as people have develop standards to use as communication. These standards such as time, length, temperature, numbers, letters, etc.. do not physically exist in nature, they are man made.